/*
 * Copyright (c) 1997, 2012, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
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package com.sun.tools.internal.ws.util;

import org.xml.sax.EntityResolver;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;

import java.io.IOException;

/**
 * {@link EntityResolver} that delegates to two {@link EntityResolver}s.
 *
 * @author WS Development Team
 */
public class ForkEntityResolver implements EntityResolver {
    private final EntityResolver lhs;
    private final EntityResolver rhs;

    public ForkEntityResolver(EntityResolver lhs, EntityResolver rhs) {
        this.lhs = lhs;
        this.rhs = rhs;
    }

    public InputSource resolveEntity(String publicId, String systemId) throws SAXException, IOException {
        InputSource is = lhs.resolveEntity(publicId, systemId);
        if(is!=null)
            return is;

        if(publicId == null) {
          // WorkAround: Ant's XMLCatalog supports public IDs only, this allows us to treat it as system IDs
          publicId = systemId;
        }

        return rhs.resolveEntity(publicId, systemId);
    }
}
